The present invention is generally related to a target device provided with a protective film and a sputtering apparatus including the target device, and more particularly to a target device provided with a protective film that protects a backing plate and a sputtering apparatus including the target device.
Currently, thin films (such as, electrodes in a semiconductor apparatus or flat display apparatus) are made using a sputtering apparatus. In a sputtering apparatus, a target device having a target plate formed from constituent materials of a thin film is disposed inside a vacuum chamber and plasma is formed inside the vacuum chamber. The ions inside the plasma are accelerated and impact the target plate so that the target plate is sputtered, and thereby a thin film is formed on a surface of a substrate.
A negative voltage is generally applied to the target plate; and thus, the target plate is attached to a metal backing plate that serves as a cathode electrode. The backing plate is disposed inside a vacuum ambience together with the target plate.
Backing plates are often constituted by aluminum, copper, or copper alloy; and a material that does not discharge much gas in a vacuum ambience is preferred. Furthermore, another desired property is that no color change or surface roughness occurs when a used target plate is exchanged for an unused target plate and then the backing plate is reused.
To accommodate such requirements, for example, a technology for forming a thin film that protects the backing plate on a surface of the backing plate surface has been proposed (see JPA No. 2002-146523).